Summary

At about 1515 on 30 January 2009, northbound freight train 6MB2,
owned and operated by Pacific National, derailed near the beginning
of a left-hand curve located near the 8.915 track km point in
Tottenham, Victoria. In total, 8 wagons derailed and about 400 m of
timber sleepered track was damaged. Damage to rolling stock was
minimal and there were no injuries as a result of the
occurrence.

At the time of the derailment, major infrastructure works
between Melbourne and Sydney were being carried out to improve the
general track condition and operating efficiency on the standard
gauge rail corridor.

Train 6MB2 derailed as it passed over a section of mainline
track in the Tottenham Yard precinct that contained a build up of
longitudinal rail stress after three consecutive days of very high
ambient temperatures. Due to the extreme weather conditions, the
Australian Rail Track Corporation had implemented heat speed
restrictions for train operators between Tottenham and Albury,
restricting trains to speeds not greater than 60 km/h.

When train 6MB2 approached the left-hand curve near the Ashley
Street Bridge, the train crew observed that a small lateral
misalignment had developed in the track. During the passage of the
train the dynamic movement of the rail vehicles added sufficient
force to increase the size of the misalignment as the train passed
over it. A container flat wagon (NQKY 34695L), 31st in the consist,
was the first vehicle to derail and it was positioned near the rear
of the train.

No evidence was found that defective rolling stock components
had contributed to the derailment and minor damage to the rolling
stock was sustained during the derailment sequence.

The investigation found that as part of the project works, the
Tottenham standard gauge passing loop was converted for mainline
operation on 28 July 2008. A safety issue was identified where this
section of track was not tested after the conversion to mainline to
determine if any residual stress was present in the rails and if
any treatments were necessary to reduce the likelihood of track
misalignments.

Other safety issues identified that creep monuments had not been
installed at the east end of the curve near where train 6MB2
derailed and the rails had not been punch marked to allow track
inspectors to detect rail creep. In addition, a record of two rail
welds carried out at the 8.351 km point on the 30 January 2009 had
not been documented for future reference. Attention to both of
these items were specific requirements of the V/Line Infrastructure
Civil Engineering Circular 3/87.

Following the derailment, the Australian Rail Track Corporation
reconstructed this section of track and replaced the timber
sleepers with concrete sleepers as part of the Tottenham to Dynon
infrastructure track upgrade.

Safety Issues

The section of track where train 6MB2 derailed, was previously utilised as the Tottenham standard gauge passing loop. It was not stress tested after slewing and welding when it was converted to mainline operation on 28 July 2008, 5 months before the derailment.

Regular monitoring and accurate measurement of rail creep was not carried out at the east end of the curve where train 6MB2 derailed in accordance with Civil Engineering Circular 3/87 - 70.2 and 70.3. Creep monuments were not installed on the east end of the curve following the work to convert the passing loop track to mainline operation in July 2008.

Punch marks were not made on the rail and documented with references to monuments at the 9 km mark following the realignment of track west of the Ashley Street rail bridge. This omission precluded the detection of rail creep that may have been present during the October 2008 maintenance inspection.